Wednesday, December 02, 2009

News---The Science of Civil War Atlanta's Archaeology

Science Digs Into Civil War Sites, Cameron McWhorter, US News and World Report Science and The Atlanta Journal-Constitution, November 29, 2009.

Just north of I-20 on Moreland Avenue in Atlanta sits an intersection on a low hill. There's a gas station and a liquor store and some other businesses, but not much else. Though you would never know it from the unremarkable view, thousands of men died here 145 years ago in one of the fiercest fights of the Civil War. Confederate Private Sam Watkins, wounded in the battle that July day in 1864, recalled bodies, horses, wagons and cannon "piled indiscriminately everywhere" and "streams of blood.""'Twas a picture of carnage and death," he wrote. It was a day and a place he would never forget.

But Atlanta did forget. Since the war, the city has sprawled out in every direction with buildings, roads and traffic, paving over this battleground and others. Today most people assume any archaeological record of the clash of two enormous armies more than 160,000 men has been obliterated by modernity. Not so fast. A small but growing number of Georgia archaeologists and history buffs are starting to use high-tech gear, ground-penetrating radar, metal detectors, new software programs and detective-style techniques to detail with amazing precision what happened when U.S. Gen. William T. Sherman made good on his promise to "make Georgia howl."

Decades ago, archaeology was about spades, notebooks and educated guesses. You found a field where you thought something might have been, and you dug pits. Trying to piece together what happened on a battlefield for several hours of one day more than a century ago seemed preposterous. This was especially true in metro Atlanta, where bulldozers have been working overtime for decades. But now this loose group of experts call them Civil War CSI are on the case. They still use historical records and spades, but they also use a whole lot more.

Garrett Silliman, a 35-year-old archaeologist at an environmental consulting firm, has started giving talks to experts in the area and in other states on new approaches that are helping find new Civil War sites and new information in this megalopolis of drywall and asphalt. "A lot of this technology has been around for years, but now it's a lot cheaper and easier to use," he told The Atlanta Journal-Constitution. "For some of us, it's becoming standard operating procedure."

The technology includes:

GIS: geographic information systems technology detailed mapping software that can give a three-dimensional view of an area, and impose old Civil War maps on modern maps.

GPS: global positioning system, which uses satellite to pinpoint the location of a found object or entrenchment.

Ground-penetrating radar. Developed by the U.S. Army to find enemy tunnels during the Vietnam War, the technology used to require a truck and many people to operate it. Today, one person can carry it on his back. The radar can find disturbances many feet underground, revealing Civil War earthworks or battles. Soil and relic testing. Lab testing can give detailed reports on everything from the age of an item to traces of blood.

Metal detectors that are far more precise than the clunky ones popular with Civil War relic hunters. Several Georgians are embracing these new tools. William Drummond, a professor at Georgia Tech's College of Architecture, has spent years promoting GIS technology for use in identifying, analyzing and preserving battlefields.

Dan Elliott, an archaeologist who has been doing Revolutionary War research and some Civil War research in coastal and central Georgia, was trained to use ground-penetrating radar about eight years ago. At the time, only four people in the state knew how to use it — and almost no one was using it for archaeology. Today, more than 20 people in the state are trained and it is a common tool for archaeologists."Basically we're stealing ideas that medical technology had 20 years ago," he said. "It gives you Superman eyes to see under the ground." Lu Ann De Cunzo, president of the Society for Historical Archaeology and a professor at the University of Delaware, said these technological advances have given archaeologists an exactitude no one could have imagined only a few years ago. "We can really fine-tune what we are seeing," she said.

The precision this technology offers is startling. To demonstrate, Silliman picked up a small plastic bag on his desk. Inside was a bullet that he recently recovered from a site at Tanyard Creek in Buckhead. Through global positioning he knew the exact location where the bullet was found. Examining its markings, he was able to tell it was a British-made bullet fired from model 1853 Enfield rifle. Because it was slightly marked, he could tell it had been rammed into a gun that had been fouled, probably from being shot a lot that day. Because the lead bullet didn't have any impact marks, he could tell it had not hit a target, but probably just traveled through the air, then dropped to the ground. Military records showed fighting at that location. Using mapping software showing modern Atlanta overlaid with Civil War fortifications, he traced back 1,100 to 1,300 yards the distance an Enfield-fired bullet would travel — to Rebel earthworks.

Silliman held up the little gray missile and declared confidently it was fired between 2 and 4 p.m. on July 20, 1864, by a retreating Confederate soldier. The Rebel missed whatever he was trying to hit. A reporter asked Silliman if he was sure. Silliman smiled slightly. "Plus or minus 120 feet," he said.

Sitting in his small but ordered office in Smyrna, Silliman pulled up on his computer a topographic map of modern Atlanta. He then superimposed historical maps of Union and Confederate defenses, soldiers' camps and where battles took place. Red lines signified Confederate areas; blue showed Union areas. Purple showed areas that have been surveyed by archaeologists. Very little of metro Atlanta was purple. Silliman, who with his lanky build and goatee could pass for a Union corporal, hopes to see that change with new technology.

He said for years traditional archaeology has focused on small sites that were inhabited for long periods, such as Native American villages. The Civil War, he said, requires a different approach especially in Georgia. Silliman, who was raised in New Hampshire but earned his graduate degree at Georgia State University, is the resident Civil War expert at Edwards-Pitman, a subcontractor that does environmental and historical assessments for companies and government agencies that are planning to develop land. Most of his work is in metro Atlanta for the Georgia Department of Transportation or agencies looking to see if any area has historical significance. Silliman insists that huge swaths of metro Atlanta do. The whole area for about a month in 1864 was one gigantic war zone. "Essentially everything from here up to Chattanooga was battlefield," he said.

That includes the low hill near the Moreland exit, and hundreds of other places where the two armies fought around Atlanta. Under the earth, evidence of the fighting survives. Douglas Scott, an archaeology professor in Nebraska nationally known as one of the pioneers in battlefield archaeology, said this technological transformation of archaeology "really has exploded, pun intended, in the last three or four years."

He said battlefield archaeologists in Europe, the eastern United States and the West have started using these tools, and now the South is embracing them. He said historical accounts, just like eyewitness testimony in a criminal case, couldn't always be trusted. "There's a precision that goes with finding stuff on the ground," he said. "Think of historians as detectives; these tools help us find the forensic evidence."